Traditional telephony presents a problem for persons who are who are D-HOH-SI. Communication by audio telephones requires each party to the call to be able to hear and/or speak to the other party in order to communicate. For hearing or speech impaired persons, audio communication is difficult or impossible, typically precluding the use of audio telephony. The availability of affordable, high-speed packet-switched communications has led to the growth in the use of Video Relay Service (VRS) communication by D-HOH-SI persons. Using VRS equipment, D-HOH-SI persons may place video calls to communicate between themselves and with hearing individuals (non-D-HOH-SI) using sign language (SL). VRS equipment enables D-HOH-SI persons to talk to hearing individuals via a sign language interpreter (SLI), who uses a conventional telephone at the same time to communicate with the party or parties with whom the D-HOH-SI person wants to communicate.
In a corrections environment (e.g., prison, juvenile detention center, etc.), communications between inmates and the outside world present a unique set of issues due to various safety, security, and confidentiality concerns for called parties, inmates, correctional officers and society in general. Audio monitoring technology employing computerized speech recognition can be used to detect keywords spoken by parties in telephone calls between inmates and the outside world that may indicate potential criminal or other prohibited activity. The pre-defined, forbidden, spoken keywords, potentially relating to planned criminal activities, may be detected, resulting in immediate actions such as termination of the call, or alerting of corrections personnel to begin real-time human monitoring of the offending call in anticipation of possible further undesirable discussions.
Because traditional audio-only telephony is adequate for communication between parties who are not D-HOH-SI, existing audio monitoring technology is suitable for communication between non-D-HOH-SI inmates and non-D-HOH-SI called parties. However, inmates classified as deaf, hard-of-hearing, or speech-impaired (D-HOH-SI) communicate with the outside world by way of Video Relay Service (VRS). VRS enables inmates to communicate with an American Sign Language (ASL) interpreter by means of ASL and video telephony. The sign language interpreter (SLI) then speaks to the called party over a standard audio phone via the public switched telephone network (PSTN).
Audio monitoring technology using real-time automated computerized speech recognition monitoring for forbidden keywords is not suitable for use with existing VRS systems because communication between inmates and sign language interpreters is transmitted visually by ASL, and not by audio.